fmax

Multi-vector Floating-point Maximum (SME2)

FMAX { <Zdn1>.<T>-<Zdn2>.<T> }, { <Zdn1>.<T>-<Zdn2>.<T> }, { <Zm1>.<T>-<Zm2>.<T> }

Maximum of 2 or 4 FP vectors.

Pseudocode Operation

No pseudocode available.

Encoding

Binary Layout
11000001
31:24
size
23:22
1
21
Zm
20:17
0101100
16:10
010
9:7
0
6
0
5
Zdn
4:1
0
0
 
Format SME2 Float
Opcode 0xC120B100
Extension SME2

Related

Other forms of fmax

  • fmax Floating-Point Maximum (Scalar)
  • fmax Vector Floating-Point Maximum
  • fmax SVE Floating-Point Maximum
  • fmax Floating-Point Maximum (Half-Precision)

More in SME2

Reference

View in Arm A64 ISA Reference ↗ Arm A64 ISA

Instruction Forms

Encoding Instruction ISA Bit pattern
0x0E403400 FMAX <Vd>.<T>, <Vn>.<T>, <Vm>.<T> A64 0 | Q | 0 | 01110 | 0 | 10 | Rm | 00 | 110 | 1 | Rn | Rd
0x0E20F400 FMAX <Vd>.<T>, <Vn>.<T>, <Vm>.<T> A64 0 | Q | 0 | 01110 | 0 | sz | 1 | Rm | 11110 | 1 | Rn | Rd
0x1EE04800 FMAX <Hd>, <Hn>, <Hm> A64 0 | 0 | 0 | 11110 | 11 | 1 | Rm | 01 | 00 | 10 | Rn | Rd
0x1E204800 FMAX <Sd>, <Sn>, <Sm> A64 0 | 0 | 0 | 11110 | 00 | 1 | Rm | 01 | 00 | 10 | Rn | Rd
0x1E604800 FMAX <Dd>, <Dn>, <Dm> A64 0 | 0 | 0 | 11110 | 01 | 1 | Rm | 01 | 00 | 10 | Rn | Rd
0xC120A100 FMAX { <Zdn1>.<T>-<Zdn2>.<T> }, { <Zdn1>.<T>-<Zdn2>.<T> }, <Zm>.<T> A64 11000001 | size | 10 | Zm | 101000 | 0100 | 0 | Zdn | 0
0xC120A900 FMAX { <Zdn1>.<T>-<Zdn4>.<T> }, { <Zdn1>.<T>-<Zdn4>.<T> }, <Zm>.<T> A64 11000001 | size | 10 | Zm | 101010 | 0100 | 0 | Zdn | 0 | 0
0xC120B100 FMAX { <Zdn1>.<T>-<Zdn2>.<T> }, { <Zdn1>.<T>-<Zdn2>.<T> }, { <Zm1>.<T>-<Zm2>.<T> } A64 11000001 | size | 1 | Zm | 0101100 | 010 | 0 | 0 | Zdn | 0
0xC120B900 FMAX { <Zdn1>.<T>-<Zdn4>.<T> }, { <Zdn1>.<T>-<Zdn4>.<T> }, { <Zm1>.<T>-<Zm4>.<T> } A64 11000001 | size | 1 | Zm | 00101110 | 010 | 0 | 0 | Zdn | 0 | 0
0x651E8000 FMAX <Zdn>.<T>, <Pg>/M, <Zdn>.<T>, <const> A64 01100101 | size | 011 | 11 | 0 | 100 | Pg | 0000 | i1 | Zdn
0x65068000 FMAX <Zdn>.<T>, <Pg>/M, <Zdn>.<T>, <Zm>.<T> A64 01100101 | size | 00 | 011 | 0 | 100 | Pg | Zm | Zdn

Description

Determine the maximum of floating-point elements of the two or four second source vectors and the corresponding floating-point elements of the two or four first source vectors and destructively place the results in the corresponding elements of the two or four first source vectors. When FPCR.AH is 0, the behavior is as follows: When FPCR.AH is 1, the behavior is as follows: This instruction follows SME2 floating-point numerical behaviors corresponding to instructions that place their results in one or more SVE Z vectors. This instruction is unpredicated.

Operation

CheckStreamingSVEEnabled();
constant integer VL = CurrentVL;
constant integer elements = VL DIV esize;
array [0..3] of bits(VL) results;

for r = 0 to nreg-1
    bits(VL) operand1 = Z[dn+r, VL];
    bits(VL) operand2 = Z[m+r, VL];
    for e = 0 to elements-1
        bits(esize) element1 = Elem[operand1, e, esize];
        bits(esize) element2 = Elem[operand2, e, esize];
        Elem[results[r], e, esize] = FPMax(element1, element2, FPCR);

for r = 0 to nreg-1
    Z[dn+r, VL] = results[r];